[HTML][HTML] DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation

E Kotula, W Faigle, N Berthault, F Dingli, D Loew… - PloS one, 2013 - journals.plos.org
E Kotula, W Faigle, N Berthault, F Dingli, D Loew, JS Sun, M Dutreix, M Quanz
PloS one, 2013journals.plos.org
The DNA-dependent protein kinase (DNA-PK) may function as a key signaling kinase in
various cellular pathways other than DNA repair. Using a two-dimensional gel
electrophoresis approach and stable DNA double-strand break-mimicking molecules
(Dbait32Hc) to activate DNA-PK in the nucleus and cytoplasm, we identified 26 proteins that
were highly phosphorylated following DNA-PK activation. Most of these proteins are
involved in protein stability and degradation, cell signaling and the cytoskeleton. We …
The DNA-dependent protein kinase (DNA-PK) may function as a key signaling kinase in various cellular pathways other than DNA repair. Using a two-dimensional gel electrophoresis approach and stable DNA double-strand break-mimicking molecules (Dbait32Hc) to activate DNA-PK in the nucleus and cytoplasm, we identified 26 proteins that were highly phosphorylated following DNA-PK activation. Most of these proteins are involved in protein stability and degradation, cell signaling and the cytoskeleton. We investigated the relationship between DNA-PK and the cytoskeleton and found that the intermediate filament (IF) vimentin was a target of DNA-PK in vitro and in cells. Vimentin was phosphorylated at Ser459, by DNA-PK, in cells transfected with Dbait32Hc. We produced specific antibodies and showed that Ser459-P-vimentin was mostly located at cell protrusions. In migratory cells, the vimentin phosphorylation induced by Dbait32Hc was associated with a lower cellular adhesion and migration capacity. Thus, this approach led to the identification of downstream cytoplasmic targets of DNA-PK and revealed a connection between DNA damage signaling and the cytoskeleton.
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